128 BYZANTINE CHURCHES CHAP. for the cruel treatment he had suffered at the hands of his jealous brother Andronicus. There, that emperor himself became a monk two years before his death/ and there he was buried on the i3th of February 1332. The monastery contained also the tomb of the Empress Irene,2 first wife of Andronicus III., and the tomb of the Russian Princess Anna3 who married John VII. Palaeologus while crown prince, but died before she could ascend the throne, a victim of the great plague which raged in Constantinople in 1417. The monastery appears once more as the scene of a great religious revival, when a certain nun Thomais, who enjoyed a great reputation for sanctity, took up her residence in the neighbourhood. So large were the crowds of women who flocked to place themselves under her rule that c the monastery of Lips and Martha' was filled to overflowing.4 The church was converted into a mosque by Phener6 Isa3 who died in 1496, and has undergone serious alterations since that time.5 Architectural Features The building comprises two churches, which, while differing in date and type, stand side by side, and communicate with each other through an archway in their common wall, and through a passage in the common wall of their narthexes. As if to keep the two churches more closely together, they are bound by an exonarthex, which, after running along their western front, returns eastwards along the southern wall of the south church as a closed cloister or gallery. The North Church.—The north church is of the normal c four column' type. The four columns which originally supported the dome were, however, removed when the building was converted into a mosque in Turkish times, and have been replaced by two large pointed arches which 1 Niceph. Greg. I, p. 461. 2 Cantacuz. I. p. 193. 3 Phrantzes, p. no. 4 Ibid, p. 141. 5 Paspates, p. 325.